tire pressure ?

well I have not weighed our unit, but then again I don't carry a 16lb sledge hammer, or a splitting maul, but I do carry only a half a tank or fresh water when on the road,and always checking the psi.we do not carry to much stuff. saw a lot of folks that do.we would hear of folks that have blowouts.thouse things I have mentioned here have servied us well, now its all happy-camping

LVJ58 wrote:
Best thing is have your coach weighed to find out the weight on the front and rear axles, then using the tire manufacturers load inflation chart inflate your tires accordingly.

Our coach with a tag axle weighs 21,230lbs loaded for travel. Using the tire manufacturers load inflation chart, 80 psi in all tires will safely support the weight of our coach.

Good luck and safe travels....

x2. This is really the only way to do it right. Playing with pressures and going by the sticker are guesses. And you don't want to guess. Weigh it, pull the chart for your tires and set psi. TMPS isn't a bad idea either.

Best thing is have your coach weighed to find out the weight on the front and rear axles, then using the tire manufacturers load inflation chart inflate your tires accordingly.

Our coach with a tag axle weighs 21,230lbs loaded for travel. Using the tire manufacturers load inflation chart, 80 psi in all tires will safely support the weight of our coach.

Good luck and safe travels....

Experiment with different tire pressures to see what works for you that's what I did and 100 lbs. all around worked for me! My manual said 85 rear and 90 front, didn't work for me! Good Luck

btilfan wrote:
this subject was probably beaten to death but I'm stumped.
I can't find any info inside the motor home for recommended tire pressure.
The sidewall on the tires say 120psi.
The dealer has 85 lbs in each tire.
They are Samson GL283A 245/70R 19.5.

coachmen liberty 2004 ford chassis.

I have not weighed the unit.

the 120-psi on your tires is the minimum inflation you need for the maximum load the tire can support. unless your load is the maximum the tires can support (which is frequently more than the chassis can support) you don't need to run 120-psi in your tires. you can run that much if you choose but if your total weight is less than the maximum weight the tires can support you will have a rough ride and may experience handling difficulties since there will be less tire tread in contact with the roadway surface.

you generally want to run the minimum inflation needed for the load the tires can support. to determine the minimum inflation you need to know what your MH weighs as it is loaded and configured for travel. this includes food, fuel, water, clothing, pets, people and other stuff. getting individual weights at each corner is preferable but sometimes hard to do so at a minimum get individual axle weights.

once you know the weight on the front axle and rear axle look at your tire sidewall. it will tell you how much weight each tire can support in a single and dual configuration. as an example you should expect to see something like this: single/2400-lbs dual/4800-lbs. your numbers on your tires will most certainly be different.

so, if your front axle weight was 3500-lbs you would be good since your two front tires can support 4800-lbs. if your front axle weight was 5000-lbs then your tires would be overloaded. if your rear axle weight was 8000-lbs you'd be good there too as your 4-tires can support 9600-lbs. but if the rear axle weight was 10,000-lbs your rear tires would be overloaded.

now that you know the weight of the MH and if the tires can support that weight how do you determine how much air to put into the tire? you consult the inflation table for the brand of tire you have. I use goodyear tires and goodyear publishes their inflation table. to use the table I find my tire size, then move to the max weight column until I find the column that has weight limits greater than what my actual weights are. the minimum inflation for that maximum load is shown.

lets use the goodyear chart, your tire size and the example weights to show you how this works. your 245/70r 19.5 tires are supporting 3500-lbs (1750-lbs per tire) in the front and 8000-lbs (2000-lbs per tire)in the rear. if you had goodyear tire the chart indicates your minimum inflation for those weights is 70-psi per tire (or 80-psi depending on the date of mfg for that tire). you can run a higher inflation but 70-psi (or 80-psi) is the minimum. get it?

so you need to get your coach weighed as described and then determine the proper minimum inflation from the Samson tire chart, not the good year chart. by the way, if you do manage to get individual corner weights you inflate all the tires on that axle to the minimum inflation for the tires carrying the heaviest load.

good luck.